In general, the bulk of the food waste or the bulk of the plant waste generated in the plant etc. are reclaimed or treated by methods such as an incineration and a dumping and so on.
However, in case of the treating method such as the landfill, the incineration, or the dumping etc., it requires a great landfill cost and a great landfill site. Thus, there is a big problem in that it causes a secondary environmental pollution.
In particular, an effluent as a high concentration wastewater is generated during the treatment process of the food waste. Since it is more difficult to process the effluent, the bulk of the effluent has been treated by an ocean dumping manner. However, according to a London convention, it is going to fundamentally ban the ocean dumping by the Korean government. Accordingly, it is expected to cost the tremendous processing expense.
Meanwhile, a waste disposal method and a solid fuel manufactured by using the same capable of perfectly recycling the waste by dewatering the food waste, mixing it with combustible additives to manufacture a solid fuel, and purifying the discharging water generated from the manufacturing process through the wastewater treatment process has been well-known in Korea Patent Registration No. 10-0661624.
That is, the disposal method of the waste includes a first waste dewatering process for dewatering the waste, a sorting process of sorting it, a crushing process, a second dewatering process, and a pulverizing process of finely pulverizing to a size of a diameter 5 mm or less, a mixing process of mixing a catalyst agent including amorphous carbonaceous powder, calcium oxide based additive, sodium based additive and solid acid catalyst with the obtained waste, drying process of drying the mixed waste until the moisture content reaches 20-30%, a second mixing process of mixing a solution obtained by mixing and melting waste, organic binder and sludge with the mixing waste having the moisture content of 20-30%, a molding process of molding a treated material obtained through the second mixing process into a solid fuel through a molding machine, a chemically and biologically treating process of chemically treating and biologically treating discharging water of waste discharged through the dewatering processes in an aerobic tank and an anoxic tank, and purifying and discharging process of purifying the discharging water through advance water treatment and discharging sludge after purifying the discharging water treated through the first step in an organic tank.
Accordingly, as described above, the food waste is dewatered, so that the moisture is set to an optimal level. Also, the amorphous carbonaceous powder and the catalyst etc. are putted into the waste to be polymerized, so that the combustible solid fuel can be produced. Moreover, the discharging water generated from the manufacturing process is purified through the chemical and biologically treating processes, so that it can recycle the food waste and the discharging water can be purified and discharged.
However, in case of the above food waste disposal method, since the water content thereof is high due to the characteristic of the food waste and large amounts of fluidal fat elements are contained in the waste, it is extremely difficult to effectively dewater the waste. Also, on account of the fluidity of the waste, it is very difficult to simply pulverize and solidify the waste through the mixing process of mixing the oxide based additive and the sodium based additive such as liquidity quicklime, slaked lime, and sodium hydroxide, etc. thereto
Further, since the moisture of the waste mixture generated during the mixing and drying processes of the waste water is not easily discharged owing to the air having the moisture inside the drying device, the drying efficiency thereof is extremely lowered. Also, since the moisture is not evenly dried inside the dried waste, there is a problem in that it is difficult to recycle the waste as a solid fuel.
In addition, in case of the above food waste disposal method, since the sewage sludge and the food waste having a low fat and oil content are solidified, there is a problem in that it is impossible to treat the floating material having a high fat and oil content.